Search results
Results from the WOW.Com Content Network
In radio transmission, transmitter power output (TPO) is the actual amount of power (in watts) of radio frequency (RF) energy that a transmitter produces at its output. [1]TPO is a concept related to effective radiated power (ERP), but refers to the power output of a transmitter, without accounting for antenna gain.
The actual output impedance for most devices is not the same as the rated output impedance. A power amplifier may have a rated impedance of 8 ohms, but the actual output impedance will vary depending on circuit conditions. The rated output impedance is the impedance into which the amplifier can deliver its maximum amount of power without failing.
The output power of a motor is the product of the torque that the motor generates and the angular velocity of its output shaft. Likewise, the power dissipated in an electrical element of a circuit is the product of the current flowing through the element and of the voltage across the element. [1] [2]
The power gain can be calculated using voltage instead of power using Joule's first law = /; the formula is: = . In many cases, the input impedance and output impedance are equal, so the above equation can be simplified to:
The red curve shows the power in the load, normalized relative to its maximum possible. The dark blue curve shows the efficiency η. The efficiency η is the ratio of the power dissipated by the load resistance R L to the total power dissipated by the circuit (which includes the voltage source's resistance of R S as well as R L):
Load regulation is the capability to maintain a constant voltage (or current) level on the output channel of a power supply despite changes in the supply's load (such as a change in resistance value connected across the supply output).
For very low-power systems, such as mobile phones, signal strength is usually expressed in dB-microvolts per metre (dBμV/m) or in decibels above a reference level of one milliwatt . In broadcasting terminology, 1 mV/m is 1000 μV/m or 60 dBμ (often written dBu). Examples. 100 dBμ or 100 mV/m: blanketing interference may occur on some receivers
The power input to the equipment will be greater owing to the less than 100% efficiency of the device. [1] [2] [3] Efficiency of a device is often defined as the ratio of output power to the sum of output power and losses. In some types of equipment, it is possible to measure or calculate losses directly.